Device for determining the size of fastener threads



FIG. 1 is a front elevation view of a device for determining the size of fastener threads incorporating my new design;

FIG. 2 is a rear elevation view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a bottom plan view thereof; and,

FIG. 7 is a perspective view thereof.

The broken line showing of structural features is included for the purpose of illustrating non-claimed subject matter and forms no part of the claimed design. 

The ornamental design for a device for determining the size of fastener threads, as shown and described. 